def _create_dispatcher(self, output):
"""Create a dispatcher for the given output.
Args:
output (str): Alert output, e.g. "aws-sns:topic-name"
Returns:
OutputDispatcher: Based on the output type.
Returns None if the output is invalid or not defined in the config.
"""
try:
service, descriptor = output.split(':')
except ValueError:
LOGGER.error(
'Improperly formatted output [%s]. Outputs for rules must '
'be declared with both a service and a descriptor for the '
'integration (ie: \'slack:my_channel\')', output)
return None
if service not in self.config or descriptor not in self.config[service]:
LOGGER.error('The output \'%s\' does not exist!', output)
return None
return StreamAlertOutput.create_dispatcher(service, self.region,
self.account_id,
self.prefix, self.config)
def test_create_dispatcher():
"""StreamAlertOutput - Create Dispatcher"""
dispatcher = StreamAlertOutput.create_dispatcher(
'aws-s3',
REGION,
FUNCTION_NAME,
CONFIG
)
assert_is_instance(dispatcher, S3Output)
def run(alert, region, function_name, config):
"""Send an Alert to its described outputs.
Args:
alert (dict): dictionary representating an alert with the
following structure:
{
'record': record,
'rule_name': rule.rule_name,
'rule_description': rule.rule_function.__doc__,
'log_source': str(payload.log_source),
'log_type': payload.type,
'outputs': rule.outputs,
'source_service': payload.service,
'source_entity': payload.entity
}
region (str): The AWS region of the currently executing Lambda function
function_name (str): The name of the lambda function
config (dict): The loaded configuration for outputs from conf/outputs.json
Yields:
(bool, str): Dispatch status and name of the output to the handler
"""
if not validate_alert(alert):
LOGGER.error('Invalid alert format:\n%s', json.dumps(alert, indent=2))
return
LOGGER.debug('Sending alert to outputs:\n%s', json.dumps(alert, indent=2))
# strip out unnecessary keys and sort
alert = _sort_dict(alert)
outputs = alert['outputs']
# Get the output configuration for this rule and send the alert to each
for output in set(outputs):
try:
service, descriptor = output.split(':')
except ValueError:
LOGGER.error(
'Improperly formatted output [%s]. Outputs for rules must '
'be declared with both a service and a descriptor for the '
'integration (ie: \'slack:my_channel\')', output)
continue
if service not in config or descriptor not in config[service]:
LOGGER.error('The output \'%s\' does not exist!', output)
continue
# Retrieve the proper class to handle dispatching the alerts of this services
dispatcher = StreamAlertOutput.create_dispatcher(
service, region, function_name, config)
if not dispatcher:
continue
LOGGER.debug('Sending alert to %s:%s', service, descriptor)
sent = False
try:
sent = dispatcher.dispatch(descriptor=descriptor,
rule_name=alert['rule_name'],
alert=alert)
except Exception as err: # pylint: disable=broad-except
LOGGER.exception(
'An error occurred while sending alert '
'to %s:%s: %s. alert:\n%s', service, descriptor, err,
json.dumps(alert, indent=2))
# Yield back the result to the handler
yield sent, output